We propose to develop a mobile health smartphone application (app) called the HEart-health Networking Aid (HENA), to help persons returning from incarceration into open society. HENA will help them manage cardiovascular disease (CVD) during their re-integration period, and in the broader context of other health and non-health related challenges they face. More then 600,000 persons are released each year from state and federal prisons to their communities and an estimated 9 million persons are released from local jails back to their communities. CVD is a frequent cause of illness and death for these ?returning persons?. Without any health interventions, many are likely to end up in Emergency Rooms at community hospitals, because most will have lost insurance coverage and are unable to maintain medication or other treatment plans once released, especially in light of the challenges in housing, food, and employment that they face. As a result, a successful intervention to help this population maintain cardiovascular health can produce broader economic and population health benefits. Recent work by the research team has shown that a patient?s social network can help that patient improve chronic disease self-management (in that case, for cardiovascular disease). That research also developed a demonstration that smart-phone app could facilitate such self-management support. This proposal seeks to apply the methods and technology from our prior research and translate it into a commercial-grade HENA smart-phone app. HENA will engage a returning person?s family and community resources to help that person improve heart health and avoid CVD. HENA allows a returning person to create a private local social network of household/family/friends that will support the patient?s heart health behaviors, such as adhering to medication, finding people and safe settings for exercise, and sharing information and positive social reinforcement. HENA will also give the returning person access to local community resources to support both health needs and the re-entry to the community. Our team brings a unique combination of leaders and experts in user-centered and social computing and behavioral science research, and experts in cardiology and CVD in inmate and returning person populations. Phase I Aims are to: 1. Define needs and opportunities for HENA social support using participatory design methods within a sample of returning persons, people from their family/friend networks, and healthcare and community support persons that are stakeholders in the success of HENA. 2. Design the HENA user interface and develop a complete HENA app prototype. 3. Conduct initial formative assessment of the HENA prototype for usability and perceived usefulness.